Whenhot,heplacedtheminanemptyoildrumwithkaukau(sweetpotato),cornandgreens.Whenhot
OutsideMukapwasbuildingafire.Oncethefirewasgoing,helaidstonesonit.Whenhot,heplacedtheminanemptyoildrumwithkaukau(sweetpotato),cornandgreens.Hethencoveredthevegetableswithbananaleavesandleftthemtosteam.
请问Whenhot,为状语从句省略吗?